During an online versus match (Face Off), the meter bar in the middle of the screen displays who is winning by the most points. To get more points, hold the whammy bar down while playing. The whammy bar gets you more points for longer notes, but on short ones it is hard to hit. Hold the whammy bar to get all of them.
Skip to the tutorials and do the Advanced Techniques section. Once complete and the screen goes back to where it gives you a choice for tutorials and practice, go directly to practice. Look at the set list. All the songs will have five stars by them and a 1,000,000 score.
When battling Lou in expert mode, strum without holding any frets until you lose. Select "Tutorial" and play the tutorial for guitar battle until the "Lesson Complete" message appears. When the next fret board appears, pause the game, and exit to return to the lesson menu. Press Red to return to the list of songs. Lou's notechart will now be set to easy mode.